The classification of fire that involves combustible metals is which class?

• A. Class B
• B. Class D
• C. Class A
• D. Class C

Answer: (B)

Fires involving combustible metals are categorized as Class D. Metals such as magnesium, titanium, and aluminum burn differently from ordinary combustibles or flammable liquids and require a special approach. Water-based extinguishing methods can react violently with many reactive metals, sometimes producing hydrogen or intense heat, so they’re not suitable. The preferred method uses a dry powder extinguishing agent designed for metal fires (or other inert smothering materials) to absorb heat and cut off the metal’s contact with oxygen. Ordinary extinguishers for wood/paper or for flammable liquids won’t effectively control metal fires, and electrical fires require a different strategy because the energy source is still involved. Always follow manufacturer guidance for the specific metal and extinguisher.